I will give you my opinion......
Shewolfz: I would go with the dirt from in front of the mausoleum..... pet's remains as well if that pet loved you.
Chagrinedgirl: Good question, I would still pay with coin and whiskey....I haven't found much about cream for a cat or a bone for a dog

but since the standard is coin and whiskey I'd stay with that payment....You must pay.....
Ccrinc: Well, the headstone is a good hint...

Usually the coffin is placed about 12 inches from the headstone, head nearest the headstone. I was shown exactly how they are laid by a cemetery worker where my relatives are buried...If you have one marker for the one grave, the coffin will be center to that marker.....If you have a husband/wife marker, each coffin would be laid side by side....each starting center to the marker....
Taking the dirt from over the heart: as long as you are in the general area....Knowing the placement of the coffin and judging the position of the head should give you a good feel for the right spot.....try to feel where the heart is as well....
Green paper: Why the color? Some things you just can't question.....I'd rather concentrate on the work and believe in the way it is presented....Also, does it really matter what type of paper? I think not.....
As far as any ritual, I kept it simple.....just as it says, I did...
.KISS....
Good Luck!